The present invention relates to an electronic equipment item comprising a housing and at least one electronic board protected against lightning, and an aircraft comprising such an electronic equipment item.
An aircraft comprises many electronic equipment items. A certain number of electronic equipment items comprise a housing in which there are a backplane board and a plurality of electronic boards, called daughterboards. Each daughterboard is fixed to the backplane board using an appropriate port. The electronic equipment item also has a connector which is electrically connected to the backplane board and which makes it possible to electrically connect the backplane board to the rest of the electronic system of the aircraft.
To protect the components present in the electronic equipment item, the latter also comprises a lightning protection board. This lightning protection board takes the form of a printed circuit onto which are fixed electronic components provided to serve as fuses and prevent the passage of the electrical currents generated by lightning to the daughterboards.
Currently, various arrangements are provided, and while these various arrangements are satisfactory from the safety viewpoint, they are not satisfactory from a bulk or maintenance point of view.
A first arrangement comprises inserting the lightning protection board between the backplane board and the connector. This arrangement leads to the creation of a separating space between the connector and the backplane board. This separating space containing the lightning protection board significantly increases the bulk of the electronic equipment item. Furthermore, replacing the lightning protection board entails dismantling all the daughterboards, then the backplane board, in order to be able to finally access the lightning protection board.
A second arrangement comprises incorporating a lightning protection board on each daughterboard. The daughterboard, of elongate form, comprises a first part comprising the components relating to the daughterboard itself and a second part comprising the components relating to the lightning protection board. This arrangement also leads to an increase in the bulk of the electronic equipment item because of the elongation of the daughterboard. Furthermore, when a lightning protection board is damaged, the entire daughterboard has to be replaced, which represents a not inconsiderable cost.